Re: Current problematic cases with immutable loginuid
On 2021-06-07 12:09, Andreas Hasenack wrote:
Hi,
I was reading up on setting loginuid immutable, and was wondering what
are the current known problematic cases.
In general, anything that requires switching a set loginuid to another
value will be blocked:
- sshd started on another port by the logged in user to debug
something, and that debug requires logging in as a different user than
the one who started it up
I could see that being an issue since that user may not have
CAP_AUDIT_CONTROL and be starting it as an unprivileged user on a port
number larger than 1024.
- container that starts up within the user's session, instead of
via
dockerd/containerd, systemd, or some other already-running daemon. I
read a lengthy bug in Redhat's bugzilla about a bad interaction with
systemd's nspawn, where apparently the container is started directly,
and thus inheriting the user's loginuid, instead of being started via
a request to systemd (the daemon)
My understanding was that any container with systemd running as PID=1 in
a PID namespace was causing this problem. This is a known and
intentional limitation. Auditd should be able to run in the initial
user namespace not under a namespaced systemd. There should be no issue
here.
The manpage mentions "certain kinds of containers", and I
assume it's
a reference to nspawn's case above.
Are there other prominent problematic situations that people have
encountered while setting loginuid immutable?
- RGB
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Richard Guy Briggs <rgb(a)redhat.com>
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